This application is directed to a slab bolster for use in reinforced concrete construction, and more particularly, to a slab bolster coupling joining a plurality of slab bolster elements to form a continuous bolster of desired length.
Slab bolsters are relatively lightweight frame members that are positioned at spaced intervals on a deck or grade within a slab form to support concrete reinforcing bar, a.k.a. rebar, prior to the pouring of wet concrete. After placing the slab bolsters in position within the slab form, rebar may be positioned so as to extend between and across the support surfaces of parallel slab bolsters. Such slab bolsters are frequently attached to other similar bolsters in a linear relationship to form a continuous bolster extending across the width of the slab form.
Known slab bolster coupling mechanisms include those shown in U.S. Pat. Nos. 3,529,392 to Adams, 4,942,714 to Langley, Jr. et al., and 5,664,390 to Sorkin, each of which can be disassembled by a simple force acting opposite the direction of assembly. Therefore these types of slab bolsters must generally be assembled and maintained in place within a slab form. Known slab bolster coupling mechanisms also include buckle type couplings such as those shown in U.S. Pat. Nos. 6,735,918 and 6,948,291 to Haslem et al., which can resist forces acting opposite the direction of assembly and thus permit pre-assembly of a continuous bolster prior to installation within a slab form, but have been found require comparatively high insertion forces in order to resist unintentional disassembly during installation or repositioning, leading to fatigue during repeated assembly of constituent slab bolster elements. Thus there is a need for a simple-to-assemble coupling providing for greater ease of insertion with a similar degree of resistance to unintentional disassembly. Moreover, there is a need for a coupling providing for occasional intentional disassembly to minimize wastage.